From the Director

Rex

 

 

 

by Rex Parker, Director

A Perfect StarQuest Weekend in Hope NJ. The 23 AAAP members who convened at the Hope Conference and Renewal Center in northern NJ Sept 22-23 had a truly stellar weekend with warm weather and the clearest skies we’ve had in a long while. The Milky Way was readily visible high overhead and many of the Messier and NGC objects we sometimes struggle to see were being picked up by nearly everyone on the observatory field. Several moderately sized portable refractors (3-5 diameter lenses) set up on equatorial and alt-az mounts turned heads all night long with remarkable displays of real-time CCD imaging. This technique, referred to as electronic-assisted astronomy (EAA) continues to develop as an area of high interest in our club. A variety of portable Schmidt-Cassegrains and Newtonian telescopes were also on display, including the novel binocular telescopes with original triangulation-finding method designed and made by member Peter Wraight.

At the October meeting we’ll ask the question – shall we continue the StarQuest tradition and request a reservation at Hope Center again for fall 2018? The low moon weekends to consider are Sept 7-8, Oct 5-6, and Nov 2-3 in 2018 – please give it some thought.

Telescopes are readied as darkness descends on the observing field at Jersey StarQuest Sept 23 in Hope NJ.

Goodbye Cassini – Now Part of Saturn. Always remember the amazing and beautiful images and the science discoveries made by Cassini and it’s project team in the nearly-20 year mission to Saturn. A good way for us to keep those memories alive is to see Saturn with our own eyes. Now the giant ringed planet is well-positioned for splendid telescopic views just after sunset this month. Members of AAAP as well as the public can see Saturn – and imagine the ghost of Cassini – through our state of-the-art telescopes at Washington Crossing Observatory each Friday night through the end of October. Members also have the privilege to be at the observatory any other night if a trained keyholder has opened and is using the facility, preferably before colder weather arrives. To participate send your request, indicating which nights you’re interested in coming to the observatory, by e-mail to keyholders@princetonastronomy.org.

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From the Program Chair

By Ira Polans

The October AAAP meeting is on the 10th at 7:30PM in Peyton Hall on the Princeton University campus. The presentation will be divided into two 30 minute parts. The first part is “The AAAP’s 2017 Total Solar Eclipse Trip to Monmouth, OR” by club member Arshad Jilani. The second part is “Astro-Imaging with Skynet” by AAAP Director, Rex Parker. The October presentations wrap-up our talks about the solar eclipse and promote a new member benefit.. The October presentations wrap our talks about the solar eclipse and promote a new member benefit.


The Great American Eclipse of August 21, 2017, is an event that amateur astronomers and others across the US will remember for a lifetime. Arshad Jilani and other AAAP team members went to Monmouth, OR, near Portland, to observe the eclipse. Since Monmouth was in the path of totality, they were able to see the eclipse as could only be observed from such locations. Arshad recorded the event and gives us an interesting personalized insight into the people, the drama, the location and of course the event itself as it unfolded for the rapturous observers. He has used a number of member photos and videos to bring the occasion to life for the rest of us

Telescopes and imaging technologies and software are essential tools of the trade to professional and amateur astronomers alike. However, for most of us breaking in to astro-imaging has high entry barriers. To provide a practical path to learning, AAAP has obtained access to Skynet, a remote astro-imaging network developed by the Univ. of North Carolina, Chapel Hill, Physics and Astronomy Dept. The Skynet telescopes typically are 16” imaging scopes with large format CCD cameras located all over the world. In this talk, approaches to remote imaging will be discussed with emphasis on Skynet. Members can begin learning hands-on remote astronomical imaging at no cost through access to Skynet provided by AAAP.

There will not be a club dinner prior to the meeting.

Looking forward to you joining us at the October meeting!

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From the Treasurer

By Michael Mitrano

The income statements and balance sheet show the AAAP’s financial results for the fiscal year that ended on June 30, 2017, and the AAAP’s financial position at the beginning and the end of the year.

You will see that the AAAP had a deficit for the fiscal year that roughly equals the amount spent on observatory upgrades. During the year, we added the Mewlon telescope with several eyepieces and replaced the computer equipment. Under the AAAP’s method of accounting, investments in equipment that has long-term benefit is shown as an expense in the year we purchase the equipment.

StarQuest also showed a significant loss. 2016 StarQuest’s revenue was lower than in past years, when the events ranged from having a strong surplus to showing a small deficit.

Membership for FY 2017 was strong, with a total of 107 members by year end. The chart on the right shows annual membership revenue, which has fluctuated with a slight downward trend.

The chart below shows AAAP reserves over the past 12 years. They grew over many years to very high levels relative to the annual expenses of the organization. In recent years we have invested more of those reserves into our program and facility.

Our cash balances and cumulative reserves are close to $15 thousand, equaling roughly two years of the association’s total average annual expenses from FY 2013 through FY 2017.

Please let me know if you have any questions about the report.

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The Cycle of Eclipses

by John Church

Many of my fellow AAAP members will have heard of the “saros”: the 18 years, 11 and one-third day cycle when eclipses of the sun and moon recur with nearly the same circumstances. To be more precise, the cycle lasts 6,585.3211 days. The reason that eclipses recur like this is that in this period there will have been 223 synodic months (new moons or full moons), 239 anomalistic months (returns of the moon to its perigee or apogee, its closest or farthest distance to earth), and 242 draconic months (returns of the moon to a particular one of its nodes, the two points where its path crosses the ecliptic every month and eclipses can happen if the sun is nearby.

This cycle was known to ancient skywatchers; the word “saros” is derived from the Sumerian “shar,” meaning “multitude” or “large number.” Its usefulness lies in the fact that if you see an eclipse of the sun or moon of a particular kind, i.e. total or partial and lasting a certain length of time, there will be a similar one 18 years, 11 and one-third days later.

Therein lies two difficulties. The major one is that in the extra one-third of a day, the earth will have rotated 120 degrees of longitude eastward from where you were the first time. In the case of a lunar eclipse, these are visible over such a large area that you might be lucky enough to see both of them without having to travel. In the case of a solar eclipse, as we all know, these are only total or annular in a very restricted path, but there is still a significant area where one can see at least a partial eclipse.

If one is patient enough to wait three whole saroses (a so-called “triple saros” or 54 years and about 31 days depending on how many leap years intervened), the same kind of eclipse will come back to roughly the same part of the earth where you were the first time. However, because of the extra days, the earth will now be in a different part of its slightly elliptical orbit and a different distance from the sun. The sun will also be at a different altitude, if visible at all. So if it’s a solar eclipse, the path will not be exactly where it was before and the duration will not be the same. However, in most cases you will still see something similar, if you are not clouded out.

I have been lucky enough to have seen several solar eclipses of about the same character separated by these intervals. The attached images, taken from https://eclipse.gsfc.nasa.gov/SEpubs/5MCSE.html (Espenak and Meeus, public domain), show these eclipse paths. I have added red dots to show where I was when these eclipses happened.

The individual saros series are in the upper left. If the series number is the same, then these two eclipses are in the same individual series but separated by one or more 18 + year intervals. A series starts with a small partial eclipse near the north or south pole and slowly progresses southward or northward until no more eclipses take place in that series. The only solar eclipse series currently active are those numbered from 117 to 156; the others occurred before or will occur after the 5000-year period of the maps.

click on photo to enlarge

The “x’s” in the diagrams are the subsolar points (where the sun is in the zenith) at the time and place of maximum eclipse, which is shown by an 8-pointed star. The Earth is oriented to show the full eclipse path, with the subsolar point always on the “meridian.” The dotted lines are where there is a 50% partial eclipse.

The first eclipse of which I have any reliable memory was the annular one of 1951. In Virginia, my father and I got up before sunrise and went to a park where we might have seen the annular phase. However, it was cloudy. Later on it did clear up and we saw a large partial eclipse.

The next one was in 1954, which was total farther north, and it was clear in the morning. We did see something like a 70% eclipse, which was still quite nice. I could not know then that in 1972 I and my growing family would see the next one in the series in New Brunswick, Canada as a fine total eclipse through high thin clouds. The one in 1954 was near the beginning of its track and the one in 1972 was near the end of its track, which made it possible to see both of these from the eastern part of North America despite the 120-degree turn in the earth mentioned earlier for two eclipses separated by one saros.

The first total I ever saw was at Old Point Comfort, Virginia, in March 1970 in a clear sky. One “triple saros” after this, there will be the eclipse of April 2024. I hope to be lucky enough to see this one as a total also, to complete one full triple cycle of totals.

In between these two was the large partial one in 1963 when I was a graduate student in Wisconsin. Again, I had no idea that I would see it as a superb total this August in Oregon with a group of club members. In a sense, this does complete a triple saros, but without having seen them both of them as totals.

Two other eclipses of memory were the annular (but nearly total) one of 1984 and the annular of 1994. I and my two sons were in Virginia in the central path in 1984 but were clouded out of the central phase. (Later on, of course, it cleared up.) The notable thing about this eclipse was how it suddenly got very dark for a few seconds and then as suddenly lightened up again. The cattle in a neighboring field were startled and vocalized.

In 1994, my workplace in Piscataway took a break around lunchtime on a Tuesday and we were treated to a very large partial. Some AAAP members may have seen this as a long-duration annular elsewhere. If so, it would be interesting to hear their stories about it, or about other totals that they may have observed.

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Biosphere 2

by Prasad Ganti

On a recent vacation to Arizona, the Grand Canyon state, I had the opportunity to visit Biosphere 2, near Tucson. It is a futuristic looking structure containing a sample of ecosystems found on Earth. Used currently for conducting experiments on the impact of climate change on an accelerated timescale, it was once a habitat for a voluntary group of people who lived in its sealed premises for two years from 1991 to 1993, as part of an experiment on the sustainability of life in such a closed, and scaled down ecosystem.

My first curiosity was why Biosphere 2 ? Where is Biosphere 1 ? I found that our planet Earth is Biosphere 1. The giant set of ecosystems sustaining life all around us. Millions or billions of members within each of the millions of species. It remains in harmony but for some extinctions from time to time, some as part of nature, and some forced upon by an intelligent specie called Homo Sapiens or the human beings. Other than quick experiments which can be done to predict how Biosphere 1 will behave in future, Biosphere 2 also serves as a laboratory for habitats which need to be setup in mankind’s quest for colonizing planets or moons in the future. To test the viability of different life support systems.

I recently read the book titled “The Human Experiment” by Jane Poynter who was one of the Biosphere residents for two years. An interesting experience and some interesting observations. I am not sure if I would give up two years of my life to stay in such seclusion, but this team did endure a lot to become the guinea pigs. There were some controversies regarding the experiment itself, but overall, it was more than a glass half full kind of scenario.

The Biosphere 2 was financed in its entirety of a quarter million dollars by Ed Bass, a Texas billionaire who is labelled as an ecopreneur, an entrepreneur who deals with ecological ventures. Putting his inherited wealth to good use, he contributed immensely towards the study of ecosystems. Covering an area of little more than three acres, it was architected as a series of space frame based structures. Space frame is a mesh of lightweight metallic bars, interspersed by glass. Double panes of glass sandwiching a shatter-resistant plastic film. It was constructed as the tightest building on the Earth. Once sealed, the atmosphere could not escape into Biosphere 1, nor anything could get in. It was tighter than the space shuttle. An engineering marvel in support of science! The pictures below were taken from my iPad pro.


The entire complex contains a habitat, a rainforest, a savannah, a desert, a marsh, an ocean, and some land for agriculture. The habitat contains living quarters for the inhabitants. Agricultural land is for growing crops for sustaining life within the sealed system. The ecosystems have been built with great care by importing the plant and live species from around the world. There are lot of equipment in the basement to control the environment in different parts of the Biosphere 2. The vast gamut of machinery is dubbed as Technosphere. There are sensors placed all over the Biosphere 2 which feed into the Technosphere below.

Once the Biosphere 2 is sealed, the pressure inside would fluctuate wildly as changing temperatures caused by changing seasons and the sunlight falling through the glass, causing the air inside to expand and contract. The Biosphere 2 needs lungs to breathe. For the Biosphere’s lungs, a round steel chamber the size of a large ice rink with a neoprene roof, was attached to the side of the Biosphere. The flexible ceiling would act like a bladder, rising as the pressure increased, and sagging as the pressure lowered. I could not think of such a need or a contraption earlier.
The team which lived inside for two years, prepared for a life in seclusion. First by being on a boat in the middle of Indian ocean for a month or so. And then staying in the Australian outback for about a year. Far from any civilization or its conveniences, it was similar to how small groups of people live in space like the Russian Space Station Mir or the International Space Station. Or in the research labs in Antarctica. Although they did all the chores like growing food, cooking, cleaning, recycling, operating the machinery by themselves, they did have gadgets for cooking, laundry etc.

The team grew starchy foods like white potatoes, sweet potatoes, rice, wheat sorghum etc. The variety in crops made the land use sustainable. No fertilizers or chemicals were used as they could contaminate the atmosphere and could make life unbearable. They were constrained in the amount of meat they could eat. They started with some livestock and nothing else could come from outside. The cattle had to multiply before being slaughtered for meat. The inhabitants had to grow all the food for their needs. As a result, they became skinny, often craving for all the nice food which the waving visitors were eating beyond the glass walls. There were some conflicts within different members of the group from time to time. It is to be expected from a small isolated group of people living together for extended periods of time. A simplistic lifestyle reminiscent of our forefathers! The experiment resulted in some species becoming extinct, which was to be expected, and more importantly proved that human beings could live.

There were a couple of occasions when there had to be an external intervention. Jane Poynter cut her finger very badly to the extent of dismembering. One of the inhabitants was a doctor. He could not do much. She had to be carried out to a hospital. She was back after a few hours. Second time was the reduction in levels of oxygen. It was later found to have been caused by concrete, which breathes in oxygen long after its curing is over. Oxygen was pumped from outside to make up for the loss. Other than these incidents, there was near perfect isolation.

There are enclosed systems like rainforests in other parts of the world like Gardens by the Bay in Singapore, but such a diverse set of ecosystems, along with life support systems all under one roof is really unique. Biosphere 2 is not sealed anymore, there are no more human experiments, only ecology related experiments conducted by visiting scientists. Administered by the University of Arizona, it is an excellent science facility which tourists can find very interesting.

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Trifinder Trouble

by Ted Frimet

It’s the end of the world as we know it.

A brief recapitulation on the status of my cats endeavor to improve the sighting accuracy of my 12 inch dobsonian telescope by way of collapsing his cat tower onto my behemoth. The cat survived. And the dob has good views. Good news, all around. As for the horizon challenge laid out by a member of another club – I am at the precipice of understanding, by way of an 80 year old scholar, that given the several concentric lines that represent each passing billion year eon, that our shared astronomical sight lines extend from one point in a horizon, to another. As a line is drawn, from the observers point to the observed, as a geometric chord across the curvature of our graph, the area under the curve is my horizon.

Hence, my answer to the esteemed gentlemen of other club grand stature is that I now proclaim “horizon” to be a relative term. Did anyone take a breath? Did you want some dressing with that word salad? Wait for it. One more verbal equivalent of the hand jiggle to get all the wiggly wigglies out!

If you fast forward to the end of this essay, you will find an embedded cat meme, produced by yours truly. I would rather you get the message, other than the fortuitous laugh. The message being, “please spay or neuter your pets”. This message comes to you, across a vast emptiness of space and time, experienced by myself, and my recently adopted feral family of one. This cat, although not personally reared to be a telescope destroyer, has recently chucked up a couple of hairballs in protest of my dobs’ temporary location in her lioness lair. However, to be fair, she is good company, and we have changed her name from “Hissy cat” to “Priss” of the Hunger Games variety. Could not ask for a better companion while hunting down faint fuzzies.

Your world is about to come to an end. And I don’t mean to relay any confidence, that this article dated September 23, 2017 has anything, coincidental to share with the end of world phenomenon espoused by others. They don’t write here, and I don’t credit ‘em being credible. Besides, I am hardly on the cusp of credibility, myself. Here is what I had to say on that: After careful calculations with a rubber band, and a ruler, I have prognosticated that a 28 meter wide asteroid will impinge operability of the ISS composting toilet, creating a causality “Do – Loop”.

No, sincerely – the only astronomical item that might coincide with the end of world event, is Asteroid J2012 TC4. The Apparent Magnitude (as seen from Earth) should be just under 22, for today. It will be closest on October 13th. As it approaches Earth with 0.10 lunar distance, the gravity will accelerate the asteroid, increasing its APMag from 16 to 13. Making it a decent target for amateur level scopes.

Unfortunately for AAAP members, the asteroid will be either below the horizon, at peak magnitude, or below the tree line. The end of the world however will have a vantage point, no matter where you observe from!

Wiggles done. Engines engaged. Warp drive committed. And now…the end of the world: PUT AWAY YOUR TELRAD. Ah got your attention. At this years Starquest we happen
across Dr. Peter Wraight, and his hand developed and simply sublime construction of astronomy grade binocular viewing devices. After being completely blown away by the reflective mirror he employed in one, and the 100mm lenses from another, I am pleased to say that you no longer have to crane your neck to get a good view of the sky thru binoculars. Could this almost be too good to be true? Well, yes. There is a slight bit of craning to be done, however, not what you would expect from Dr. Wraight.

Peter has developed a finder. You decide on a target in the night sky, and pick two guide stars of magnitude 3 or brighter. You then can either calculate, or use his NGC guide book (with pre-calculations) to obtain, a reference angle. He has written program code to doggedly convert right ascension/declination into his new Trifinder system.


As pictured above on our finder disc, two sides of a triangle (not shown), one leg ends at one guide star, the other leg – the other star. And at their vertices you will find your target. Easy Peasee. And if you didn’t get it the first time, the vertice angle is formed by the two legs. On Peter’s finder, one leg is calibrated and can span up to 18 degrees with illuminated dots for each degree, while the other is represented by a small illuminated line pointing toward three illuminated dots and spans 22 degrees. The finder incorporates a simple lens and a semi reflective perspex disc to effectively project an infinity image of this “triangle” on the sky above. Move the dob so the end points are on the guide stars, and Wa-La! – target acquired at the vertice. The seeing is the believing! I’d write more on The Trifinder, however, we should all encourage Dr. Peter Wraight to publish his work, on the web for all to know and tell.

Meme as promised:

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Snippets

compiled by Arlene & David Kaplan

-BBC, Sky & Telescope

-BBC, Sky & Telescope

Florence: Largest asteroid in century to safely fly by Earth
The largest asteroid in more than a century is set to pass by Earth at a relatively close distance of 4.4 million miles (7 million km), Nasa says. Florence measures 2.7 miles (4.4km) in diameter and will not pose a threat to Earth for centuries to come…more

Credit- Swansea Univ./CERN

Credit- Swansea Univ./CERN

Swansea scientists make antihydrogen breakthrough
A team from Swansea University is one step closer to answering the mysteries of antimatter and the Big Bang after making a scientific breakthrough.
Scientists from the university’s College of Science have created and measured the properties of antihydrogen for the first time…more

Chicxulub Crater -BBC

Chicxulub Crater -BBC

Asteroid strike made ‘instant Himalayas’
Scientists say they can now describe in detail how the asteroid that wiped out the dinosaurs produced its huge crater.
The reconstruction of the event 66 million years ago was made possible by drilling into the remnant bowl and analyzing its rocks…more

Elon Musk - NYT

Elon Musk – NYT

Elon Musk’s Mars Vision
ADELAIDE, Australia — Elon Musk is revising his ambitions for sending people to Mars, and he says he now has a clearer picture of how his company, SpaceX, can make money along the way. The key is a new rocket…more

The LIGO and Virgo detectors -NYT

The LIGO and Virgo detectors -NYT

New Gravitational Wave Detection From Colliding Black Holes
In another step forward for the rapidly expanding universe of invisible astronomy, scientists said on Wednesday that on Aug. 14 they had recorded the space-time reverberations known as gravitational waves from the collision of a pair of black holes 1.8 billion light years away from here…more

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